1. Field of the Invention
The present invention relates to a semiconductor apparatus configured to electrically connect a semiconductor chip and a wired board, and a producing method of the semiconductor apparatus.
2. Description of the Related Art
Japanese Patent Laid-Open No. 9-260536 (hereinafter, referred to as Patent Document 1) proposes a semiconductor apparatus provided with a semiconductor chip, and a flexible wired board arranged on a main surface of the semiconductor chip through the elastomer.
An aperture part is formed in the flexible wired board, and a lead part of a wiring is arranged in the aperture part. An electrode pad of the semiconductor chip whose surface is directed downward is electrically connected to the lead part.
An external terminal is included on a surface of the flexible wired (hereinafter, referred to as an external terminal-mounted surface) in the opposite side of a surface on which the semiconductor chip is mounted. The electrode pad of the semiconductor chip and the lead part which are arranged in the aperture part of the wired board are covered by sealing material made of insulating resin.
In such a semiconductor apparatus, the electrode pad of the semiconductor chip and the lead part of the wired board are connected in the aperture part provided in the wired board. As a result, an external terminal can not be arranged around just below the electrode pad of the semiconductor chip, for example, within 0.75 mm from just below the electrode pad.
Year by year, since the operation rate of the semiconductor apparatus has been increased, if the distance from the electrode pad of the semiconductor chip, e.g. a wiring length, becomes long, the operation rate may be lowered. Thus, there is a need to largely shorten the wiring length of the semiconductor apparatus to obtain favorable electrical characteristics.
Since the external terminal can not be arranged around just below the electrode pad of the semiconductor chip, the number of the external terminals, which are arranged in an area of the wired board in which the semiconductor chip is mounted, may have been reduced. The number of the external terminals of the semiconductor apparatus has been increased, and it becomes necessary to arrange the external terminals outside the above area, so that the area of the wired board may become larger.
If the area of the wired board becomes larger, a package size of the semiconductor apparatus is enlarged. Further, if the area of the wired boards becomes larger, the number of the wired boards to be produced at a time is decreased when the wired board is produced, and the cost of the wired board is also increased.
In the semiconductor apparatus according to Patent Document 1, the semiconductor chip is mounted on the wired board by using elastomer (elastic material) to improve the reliability of the semiconductor apparatus when the installation to a motherboard and the like is performed.
As described above, it is possible to reduce the stress that is caused by the difference between the thermal expansion coefficients, and to improve the reliability of the semiconductor apparatus when an installation to a motherboard is performed by mounting the semiconductor chip on the wired board by using elastomer. However, the elastomer is expensive material, so that the production cost of the semiconductor apparatus may be increased.